One who habitually packs crap(poo) in his or her butt forcefully and then walks about in public spaces. It is important to note that the origin of said crap(poo) is generally of a specific species of muskrat that has a particularly bitter taste.

He is one of damn crappackers. That is why he walks like one of his legs is longer than the other and appears to achieve orgasm every quarter mile or so.